The need for a manual can opener capable of being operated by such a person has been recognised in the past. In the UK Patent Application GB 2161449A there is disclosed a can opener operable by a single hand. In essence this comprises a main handle member on which a cutting wheel is slidably supported, a second handle member pivoted to the main handle member and operable to effect rotation of a drive wheel through a one-way ratchet mechanism, and a third handle member or lever pivoted to the main handle member and operable through the agency of a toggle mechanism to cause the cutting wheel to slide into and out of the nip position. One pair of the three handle members is required for bringing the cutting wheel into the nip position, and a different pair for effecting the cutting operation. This opener is, therefore, of complex construction, is comparatively expensive to manufacture and is not simple to use.